Patent GB-384781-A (GB)
Title: Improvements relating to machines for the production of transmission chains
IPC: B21L9/00
Filed: 1931-11-28
Abstract: 384,781. Making chains ; operating clutches. RENOLD & COVENTRY CHAIN CO., Ltd., ICKE, J. H., and POTTS, C. J., Spon End Works, Coventry. Nov. 28, 1931, No. 33036. [Classes 83 (ii) and 83 (iv).] Assembling force-fits.-A machine for assembling roller chains comprises means for feeding inner link combinations step by step and locating them with the axes of their bushes in a horizontal plane and in correct spaced relation, and stations at which jointing studs are inserted into the bushes and side-plates are positioned at the sides of the links and then assembled with the jointing studs. Inner link assemblies 24, Fig. 29, are fed to a guideway 20 from a shoot 21, which may be of the form shown in Fig. 12 of Specification 295,439, [Class 83 (ii), Metal articles &c.], and are fed forward intermittently by a rack 26 which performs a movement equal to twice the pitch of the chain while in engagement with the links, and is then raised, retracted, lowered into engagement and again moved forward. The rack 26, Fig. 13, is integral with a member 66, which is moved horizontally by a cam 94 on the main shaft 62, a follower 92, links 90, 88, 86, a spindle 84, arm 82, and pin 76, the rearward movement being effected positively while the forward feed motion is effected by a spring. The bracket 70 carrying the slide 66 is reciprocated vertically from a cam 100 through a lever 96. Faulty feeding or operation at the different stations of the machine is adapted to prevent the forward movement of the rack, which sets a stop device into operation to release the main clutch. The release of the clutch is effected when a stop 252, Fig. 25, on a lever 250 comes into the path of an inclined projection 238 on the sliding member of the clutch. A cam 248 allows the lever 250 to rock under the action of a spring normally to move the stop from the path of the projection, but such movement is prevented if a reciprocating bar 240 is checked in its movement and is brought in the path of the lever 250. A latch 260, Fig. 13, passes at its lower end through a slot in the bar 240 but is rocked clear thereof against the action of a spring 262 by an extension of the arm 86 if the latter and the feed slide perform their normal movements, but in the event of the feed slide being stopped the latch prevents movement of the bar 240 and the clutch is thrown out. The links are fed to the first station A, Fig. 1, where they are acted on between a ram 30 and an anvil 32 to bring them to a uniform width and remove burrs. In the absence of a link, or of a roller therefrom, spring-pressed feelers 226 on the rack are depressed and contact the anvil 32 to stop the rack and declutch the machine. At the station B, Figs. 1 and 19, studs are fed from a hopper through two tubes 110 to one of a series of pairs of radially disposed holes in a plate 112 forming a magazine of thickness equal to the length of a stud, and intermittently rotated by a pawl 120 pivoted to the rack 66 and engaging ratchet teeth 118 on the plate. If a short or long stud is fed, part of a stud projects from the plate and stops the rack and therefore the machine. The links are centred by spring-pressed plungers 42 on a ram 40, plungers 38 on a ram 36 then moving forward to insert the studs 34 until they abut against the plungers 42, when both pairs of plungers move in the same direction until the studs are in position. In the absence of a stud, or if one of small diameter is inserted, plungers 230, Fig. 24, similar to the plungers 226, strike an abutment 235 to stop the rack and declutch the machine. Side-plates 44, 58 may be secured at one station, but are preferably secured in turn at successive stations C, D. Plates 58 are fed from a magazine 174, Fig. 11, and are conveyed on end to the guideway 20 by a reciprocating feed slide 176. Spring- pressed plungers 56 pass through holes in the plates and enter conical holes in the studs, the ram 54 then advancing to force on the plates while the plungers retire within the ram. If a side-plate is absent, the slide 176 performs a greater movement than the normal, and actuates a device which prevents reciprocation of the bar 240 to stop the machine, a similar device being provided at station C. A side-plate is omitted periodically so that the chain is formed in a series of separate lengths when a cam block 188 on a sprocket chain 186 moves a plunger 198 to push the stack back into the magazine, the plunger also preventing excess movement of the slide 176 to render the stop mechanism inoperative. A similar manually controlled plunger is provided at station C to omit a side-plate at will. The chain is pressed to uniform width between rams 60, Figs. 1 and 22, with meeting faces 61 and plugs 201 at a sufficient depth below the work faces to accommodate the protruding portions of the studs in the recesses so formed. The completed chain is conveyed from the machine by an intermittently rotated sprocket wheel.